Portable battery pack



FIG. 1 is a front perspective view showing a first embodiment of the portable battery pack;

FIG. 2 is a top view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right side thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a rear view thereof;

FIG. 7 is a bottom view thereof;

FIG. 8 is a front perspective view showing a second embodiment of the portable battery pack;

FIG. 9 is a top view thereof;

FIG. 10 is a front view thereof;

FIG. 11 is a right side thereof;

FIG. 12 is a left side view thereof;

FIG. 13 is a rear view thereof; and,

FIG. 14 is a bottom view thereof.

The broken lines shown in the drawings are included for the purpose of illustrating unclaimed portions of the portable battery pack and form no part of the claimed design. 

CLAIM The ornamental design for a portable battery pack, as shown and described. 